/*
  将下面异步代码使用 Promise 的方法改进
  尽量用看上去像同步代码的方式
  setTimeout(function () {
    var a = 'hello'
    setTimeout(function () {
      var b = 'lagou'
      setTimeout(function () {
        var c = 'I ♥ U'
        console.log(a + b +c)
      }, 10)
    }, 10)
  }, 10)
*/


const promise1 = new Promise((resolve, reject) => {
  setTimeout(() => {
    resolve('hello')
  }, 10)
})
const promise2 = new Promise((resolve, reject) => {
  setTimeout(() => {
    resolve('lagou')
  }, 10)
})
const promise3 = new Promise((resolve, reject) => {
  setTimeout(() => {
    resolve('I ♥ U')
  }, 10)
})

Promise.all([promise1, promise2, promise3]).then(data => {
  const target = data.join('')
  console.log(target)
})
